78687

α-Aminoisobutyric acid

analytical standard

• Synonym(s): 2-Methylalanine, Aib
• Linear Formula: (CH₃)₂C(NH₂)COOH
• CAS Number: 62-57-7
• Molecular Weight: 103.12
• Beilstein: 506496
• MDL number: MFCD00008049

Properties

• grade: analytical standard
• Quality Level: 100
• technique(s): HPLC: suitable; LC/MS: suitable; liquid chromatography (LC): suitable; mass spectrometry (MS): suitable
• mp: ≥300 °C
• application(s): clinical; food and beverages
• format: neat
• SMILES string: CC(C)(N)C(O)=O
• InChI: 1S/C4H9NO2/c1-4(2,5)3(6)7/h5H2,1-2H3,(H,6,7)
• InChI key: FUOOLUPWFVMBKG-UHFFFAOYSA-N

Description

General description

α-Aminoisobutyric acid (AIB; 2‑aminoisobutyric acid, α‑methylalanine) is a non‑proteinogenic amino acid with the formula H2N‑C(CH3)2‑COOH that strongly promotes helical conformations in peptides.

It is rare in nature but occurs in certain fungal peptide antibiotics (peptaibols) such as alamethicin, where AIB-rich sequences contribute to membrane activity.Testing AIB is important because it is used as a tracer of amino acid transport and as a sensitive marker of blood–brain barrier permeability changes in experimental models.

In metabolic studies, AIB can be measured in urine as an end‑product of pyrimidine metabolism, and some individuals exhibit elevated excretion due to inherited traits, making quantification relevant for biochemical assessment. Additionally, detecting AIB helps identify peptaibiotics in microbial or environmental samples, since AIB is a specific marker residue for this peptide class.

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